Clin Infect Dis. 2021 Apr 26:ciab361. doi: 10.1093/cid/ciab361. Online ahead of print.
In a large cohort of US healthcare personnel (HCP) without prior COVID-19 infection, 94,382 doses of mRNA COVID-19 vaccine were administered to 49,220 individuals. The adjusted vaccine effectiveness following two doses of each of the two available brands of mRNA vaccine exceeded 96%.